URL path with colon (":") results in 404 not found on POST?

[dwinston]

First Check

• I added a very descriptive title to this issue.
• I used the GitHub search to find a similar issue and didn't find it.
• I searched the FastAPI documentation, with the integrated search.
• I already searched in Google "How to X in FastAPI" and didn't find any information.
• I already read and followed all the tutorial in the docs and didn't find an answer.
• I already checked if it is not related to FastAPI but to Pydantic.
• I already checked if it is not related to FastAPI but to Swagger UI.
• I already checked if it is not related to FastAPI but to ReDoc.

Commit to Help

• I commit to help with one of those options 👆

Example Code

from fastapi import FastAPI

app = FastAPI()

@app.post("/items:queue")
def queue_new_item(item: dict):
    return "An item has been queued for later inclusion."

Description

• Open the browser and POST /items:queue
  • For example, go to http://127.0.0.1:8000/docs#/default/queue_new_item_items_queue_post
  • Click to Try it out
  • Click to Execute (default request body of {} is fine)
• I expect the string response "An item has been queued for later inclusion."
• I get a 404 not found response, with JSON body {"detail": "Not Found"}

Operating System

macOS

Operating System Details

No response

FastAPI Version

0.78.0

Python Version

Python 3.9.12

Additional Context

No response

[dwinston]

I realize this may be an issue upstream with Starlette, so I have started a discussion topic there: encode/starlette#1673.

[Kludex]

This is solved on Starlette 0.20.2.

FastAPI still doesn't support that Starlette version.

Note: By the time this was written, FastAPI is on version 0.78.0.

[yuanjie-ai]

[bodograumann]

Duplicate of #4892